The Intel Poulsbo Chipset, also known by its official names "GMA 500" and "Intel System Controller Hub US15W", is typically found on boards for the Atom Z processor series. It embeds a PowerVR SGX 535 graphics core developed by Imagination Technologies and then licensed by Intel. Its major advantages include the hardware decoding capability of up to 720p/1080i video content in various state-of-the-art codecs, e.g. H.264.

As the graphics hardware was not developed by Intel themselves, the standard Intel drivers do not work with this hardware. Furthermore, at least two different accelerated Linux drivers for this hardware exist, each of which have major problems. Alternatively, there is a generic framebuffer driver solution, but this is unaccelerated.

On this page you find comprehensive information about how to get the best out of your Poulsbo hardware using Arch Linux.

Drivers: Advantages and Disadvantages

Kernel's psb-gfx module

With kernel 2.6.39, a new psb_gfx module appeared in the kernel developed by Alan Cox to support Poulsbo hardware. Currently this is very rudimentary but the development is very active and this should get better and better with upcoming kernels.

Note: As of kernel 3.3.rc1 the driver has left staging and been renamed gma500_gfx.[1]

Advantages

Native resolution (1366x768) with early KMS (on Asus Eee 1101HA)

Up to date kernel and Xorg

2D acceleration

Nothing to do to make it work

Disadvantages

Did not manage to get native resolution (e.g 1366x768)

Buggy backlight control (Fixed in Linux 3.0.0)

No 3D acceleration possible

Poor performances (use mplayer with x11 or sdl so fullscreen video will be quite slow)

PSB/GMA500 Driver

Advantages

Native resolution

2D acceleration

Possible 3D acceleration with work and luck - Fedora, as well as Ubuntu, have this [2]

Backlight control possible

Disadvantages

Performance not on par with IEGD (Youtube videos play smoothly at 360p, perhaps 480p, but no higher)

Installing IEGD-enabled kernel

Installing IEGD binary drivers

tbd

Troubleshooting Xorg 1.6

Driver cannot be found

If X complains that the driver cannot be found, you may have the FBDEV driver specified in xorg.conf file, but the FBDEV driver is not installed as described in above. Revert back to "vesa" by finding the line with the video driver - fbdev - and alter it,

Driver "fbdev"

to

Driver "vesa"

Then make sure to follow the steps in the aforementioned section on installing FBDEV.

Taking Advantage of non-FBDEV/VESA Driver

Set backlight brightness

This has only been tested with the PSB driver

This is pertinent to machines with built-in LCD screens, not to devices such as the Fit-PC

With a driver installed and loaded (via modprobe or at boot), all that is needed to set the brightness is sending a number (0-100) to

/sys/class/backlight/psblvds/brightness

This obviously requires sysfs to be enabled in the kernel, as it is in the Arch Linux kernel.

An example: to set display to minimal brightness, issue this command as root:

echo 0 > /sys/class/backlight/psb-bl/brightness

Or, for full luminosity:

echo 100 > /sys/class/backlight/psb-bl/brightness

A very short script is available to do this with less typing written by mulenmar.